Normal Cardiac Troponin Research Articles

Association between cardiac troponin I concentrations and electrocardiographic abnormalities in dogs with blunt trauma.

To determine whether a normal cardiac troponin I (cTnI) concentration and normal ECG on entry rule out the development of a clinically significant cardiac arrhythmia (CSCA, defined as an arrhythmia requiring anti-arrhythmic treatment) in dogs that have sustained blunt trauma. Prospective, observational study. Client-owned dogs were enrolled between January 2015 and November 2016. University teaching hospital. Forty-seven client-owned dogs with a history of witnessed or suspected blunt trauma within 24hours prior to presentation to the hospital. On admission to the emergency service, dogs had a standard 3-lead ECG and cTnI concentration (using a veterinary point-of-care device* ) performed. Animal Trauma Triage (ATT) scores, Modified Glasgow Coma Scale (MGCS), and the details regarding the nature and timing of the injury were recorded. The patients were monitored in the ICU for a minimum of 24hours on continuous ECG telemetry. Cardiac rhythm was monitored every hour, and any abnormalities were noted. The need for anti-arrhythmic therapy was recorded. There were no treatment interventions. Five of 47 dogs (10.6%) developed a CSCA during hospitalization after sustaining blunt trauma. A normal entry ECG and normal cardiac troponin concentration on entry had a 100% negative predictive value (NPV) for ruling out the development of a CSCA, although a normal cardiac troponin concentration alone also had an NPV of 100%. A normal entry ECG had an NPV of 95.3%. The prognosis for survival to discharge was 89.4% in this study population (42/47 dogs). In dogs with blunt trauma, an entry cTnI concentration or a combination of cTnI and ECG on entry may be useful in determining which patients are at a higher risk for the development of CSCA during the first 12 to 24hours after the trauma.

Association between intraoperative hypotension and postoperative myocardial injury in patients with prior coronary stents undergoing high-risk surgery: a retrospective study.

We conducted a single-center retrospective study to evaluate the effects of intraoperative hypotension (IOH) on postoperative myocardial injury during major noncardiac surgery in patients with prior coronary stents with preoperatively normal cardiac troponin I levels. Although IOH is assumed to increase the risk of postoperative myocardial injury in patients with prior coronary stents, the level and duration of hazardous low blood pressure have not been clarified. Of 2517 patients with prior coronary stents undergoing noncardiac surgery between January 2010 and March 2017, we analyzed 195 undergoing major surgery (vascular, abdominal, and thoracic surgery) who had a normal preoperative high-sensitivity cardiac troponin I (hs-cTnI) level and were followed up postoperatively within 3days. Postoperative myocardial injury was defined as a hs-cTnI level greater than the 99th percentile reference value. Primary IOH exposure was defined as a decrease of ≥ 50%, 40%, or 30% from the preinduction mean blood pressure. Additional definition of IOH was absolute mean blood pressure < 70, < 60 or < 50mmHg. Multivariate logistic regression was used to model the exposure and myocardial injury. Myocardial injury occurred in 53 (27.2%) cases. The predefined levels of IOH were not significantly associated with postoperative myocardial injury, but intraoperative continuous inotropes/vasopressors use was significantly higher in patients with myocardial injury (P = 0.004). Operation time ≥ 166min (OR = 2.823, 95% CI 1.184-6.731, P = 0.019) and abdominal vascular surgery (OR = 2.693, 95% CI 1.213-5.976, P = 0.015) were independent risk factors for myocardial injury. Although patients with prior coronary stents with normal hs-cTnI levels did not show association between varying levels of IOH and postoperative myocardial injury after noncardiac surgery, intraoperative need of continuous inotropes/vasopressors was higher in patients with postoperative myocardial injury. Abdominal vascular surgery and surgical time were independent risk factors for myocardial injury after surgery.

Implications of Abnormal Troponin Levels With Normal Right Ventricular Function in Normotensive Patients With Acute Pulmonary Embolism.

Among patients with pulmonary embolism (PE), various permutations of normal or abnormal cardiac troponin results and normal or abnormal echocardiographic right ventricular function are encountered in clinical practice. We aimed to explore whether there is a true gradient of risk based on troponin and echocardiographic results. This study included normotensive patients with PE from the PROgnosTic valuE of CT scan in hemodynamically stable patients with acute symptomatic pulmonary embolism (PROTECT) study. Patients were categorized as having -Troponin/-Echo, -Troponin/+Echo, +Troponin/-Echo, and +Troponin/+Echo. The primary outcome was 30-day “complicated course,” including death from any cause, hemodynamic collapse, or recurrent PE. Secondary outcomes included individual adverse event rates. Of the 834 patients who had echocardiographic and troponin results, 569 patients (68%) had -Troponin/-Echo, 126 patients (15%) had -Troponin/+Echo, 74 patients (8.9%) had +Troponin/-Echo, and 65 patients (7.8%) had +Troponin/+Echo. The incidence of 30-day complicated course was 4.6% in patients with -Troponin/-Echo, 11.9% in patients with -Troponin/+Echo, 13.5% in patients with +Troponin/-Echo, and 16.9% in patients with +Troponin/+Echo (P for trend <0.001). In the subgroup of patients with a high-risk sPESI (i.e., intermediate-risk according to the ESC guidelines) (n = 527), the incidence of 30-day complicated course was 14.9% in patients with -Troponin/+Echo, 18.5% in patients with +Troponin/-Echo, and 17.5% in patients with +Troponin/+Echo (P for trend <0.01). In patiens with PE, there seems to be a risk gradient based on troponin and echocardiographic results. This study did not detect a significant risk difference in those with +Troponin/-Echo compared with -Troponin/+Echo.

Use of the Clinical Examination in the Diagnosis of Cardiac Syncope.

Patient history: Age at first syncopal episode older than 35 years = 3.3 History of atrial fibrillation or flutter = 7.3 Known severe structural heart disease = 3.3 to 4.8 Dyspnea prior to syncope = 3.5 Chest pain/angina prior to syncope = 3.4 to 3.8 Cyanotic during syncope = 6.2 Diagnostic tests: High-sensitivity cardiac troponin T > 42 pg/mL = 5.1 High-sensitivity cardiac troponin I > 31.3 pg/mL = 5.4 NT-proBNP ≥ 210.5 pg/mL = 47 NT-proBNP > 1966 pg/mL = 5.8 BNP > 302 pg/mL = 6.3 Multivariable evaluation: Heart disease, abnormal ECG, or both = 2.3 EGSYS score 3 or more = 2.8 to 3.3 Vasovagal score less than −2 = 1.7 to 8.6 Patient history: Age at first syncopal episode 35 years or younger = 0.13 Diagnostic tests: Normal cardiac troponin T or I = 0.15 to 0.39 Normal BNP level = 0.16 to 0.21 Multivariable evaluation: EGSYS score less than 3 = 0.12–0.17 Absence of heart disease, abnormal ECG or both = 0.20 Vasovagal score −2 or more = 0.10–0.84 Syncope or transient loss of consciousness is a common problem seen in the emergency department (ED), accounting for 1% to 1.5% of ED visits annually.1 Cardiac syncope caused by cerebral hypoperfusion secondary to cardiopulmonary events such as arrhythmia or structural heart disease, accounts for 5% to 21% of syncope events.2 Cardiac syncope is associated with an increased risk of premature death and cardiac events.3, 4 It is therefore important for emergency providers to differentiate cardiac syncope from other causes. This systematic review by Albassam et al.5 evaluated patient characteristics, physical examination findings, and diagnostic tests to identify cardiac causes of syncope. The authors searched the MEDLINE, Embase, CINAHL, and Cochrane databases, selecting 11 studies that met inclusion and exclusion criteria. Each study included at least 10 subjects aged 12 years or older, for a total of 4,317 patients. Studies were assigned levels of evidence developed for the Rational Clinical Examination series.6 Several historical factors were associated with an increased likelihood of cardiac syncope including age at first syncopal episode 35 years or older; history of atrial fibrillation or flutter; known severe structural heart disease; dyspnea or chest pain prior to syncope; and witnessed cyanosis during syncope. An elevated cardiac troponin T or I and an elevated B-type natriuretic peptide (BNP) both modestly increased the probability of cardiac syncope. Factors that decreased the probability included age less than 35 years at first syncopal episode; normal cardiac troponin T or I; and normal BNP. Combinations of findings such as Evaluation of Guidelines in Syncope Study (EGSYS) score ≥ 3; vasovagal score < −2; and abnormal electrocardiogram, heart disease, or both were more useful when absent than when present. The results of this review should be interpreted cautiously. Included studies generally defined cardiac syncope based on cardiologist judgment. Five of 11 studies included specialty referral populations or inpatients, leading to the potential for spectrum bias. Applying these results to a general ED population might lead to additional testing or interventions in patients who have lower risk of cardiac syncope than the studied population. Misclassification may have further skewed the results as patients with unexplained syncope were excluded from several studies. Many of the clinical findings resulted from single studies. Studies often included a wide age range of patients despite the incidence of syncope, related ED visits, and serious outcomes increasing sharply after the age of 60.7 Cardiac biomarkers such as troponin or BNP testing appear to be an attractive diagnostic option, however, they did not rule in or rule out cardiac syncope. Moreover, these cardiac biomarkers were likely used to diagnose cardiac syncope leading to incorporation bias. ACEP clinical policy, appreciating these limitations, suggests a risk stratification approach focusing on patient history and physical examination to avoid unnecessary testing and hospital admissions.1 In summary, the accurate diagnosis of cardiac syncope is helpful in determining an appropriate plan of care. While no single variable can independently diagnose or exclude cardiac syncope, several clinical findings may be used cohesively to help guide health care providers.

Can Emergency Physician Gestalt "Rule In" or "Rule Out" Acute Coronary Syndrome: Validation in a Multicenter Prospective Diagnostic Cohort Study.

Chest pain is a common problem presenting to the emergency department (ED). Many decision aids and accelerated diagnostic protocols have been developed to help clinicians differentiate those needing admission from those who can be safely discharged. Some early evidence has suggested that clinician judgment or gestalt alone could be sufficient. Our aim was to externally validate whether emergency physician's gestalt could "rule in" or "rule out" acute coronary syndromes (ACS). We performed a multicenter prospective diagnostic accuracy study including consenting patients presenting to the ED in whom the physician suspected ACS. At the time of arrival, clinicians recorded their perceived probability of ACS using a 5-point Likert scale. The primary outcome was a diagnosis of ACS, defined as acute myocardial infarction or major adverse cardiac events within 30 days. A total of 1,391 patients were included; 240 (17.3%) had ACS. Overall, gestalt had fair diagnostic accuracy with a C-statistic of 0.75 (95% confidence interval= 0.72 to 0.79). If ACS was "ruled out" in the 60 (4.3%) patients where clinicians perceived that the diagnosis was "definitely not" ACS, a sensitivity of 98.0% and negative predictive value of 95.0% could have been achieved. If ACS was only ruled out in patients who also had no electrocardiographic (ECG) ischemia and a normal initial cardiac troponin (cTn) concentration, 100.0% sensitivity and NPV could be achieved. However, this strategy only applied to 4.1% of patients. If patients with "probably not" ACS who had normal ECG and cTn were also ruled out (n=418, 30.8%), sensitivity fell to 86.2% with 99.2% NPV. Using gestalt "definitely" ACS to rule in ACS gave a specificity of 98.5% and positive predictive value of 71.2%. Clinician gestalt is not sufficiently accurate or safe to either rule in or rule out ACS as a decision-making strategy. This study will enable emergency physicians to understand the limitations of our clinical judgment.

Free fatty acids as a marker for predicting periprocedural myocardial injury after coronary intervention

BackgroundPrevious studies have revealed that plasma levels of free fatty acids (FFAs) are related to cardiovascular risk. However, whether FFAs could predict periprocedural myocardial injury (PMI) following percutaneous coronary intervention...

Risk stratification and role for additional diagnostic testing in patients with acute chest pain and normal high-sensitivity cardiac troponin levels.

BackgroundNormal high sensitivity cardiac troponin (hs-cTn) assays rule out acute myocardial infarction (AMI) with great accuracy, but additional non-invasive testing is frequently ordered. This observational study evaluates whether clinical characteristics can contribute to risk stratification and could guide referral for additional testing.Methods918 serial patients with acute chest pain and normal hs-cTnT levels were prospectively included. Major adverse cardiac events (MACE) and non-invasive test results were assessed during one-year follow-up. Patients were classified as low and high risk based on clinical characteristics.ResultsMACE occurred in 6.1% of patients and mainly comprised revascularizations (86%). A recent abnormal stress test, suspicious history, a positive family history and higher baseline hs-cTnT levels were independent predictors of MACE with odds ratios of 16.00 (95%CI:6.25–40.96), 16.43 (6.36–42.45), 2.33 (1.22–4.42) and 1.10 (1.01–1.21), respectively. Absence of both recent abnormal stress test and suspicious history identified 86% of patients. These patients were at very low risk for MACE (0.4% in 30-days and 2.3% in one-year). Despite this, the majority (287/345 = 83%) of additional tests were performed in low risk patients, with <10% abnormal test findings. The diagnostic yield was significantly higher in the remaining higher risk patients, 40% abnormal test findings and a positive predictive value of 70% for MACE. Similar results were observed in patients without known coronary artery disease.ConclusionsClinical characteristics can be used to identify low risk patients with acute chest pain and normal hs-cTnT levels. Current strategies in the emergency department result in numerous additional tests, which are mostly ordered in patients at very low risk and have a low diagnostic yield.

False-positive Troponin I Assay Elevation Due to Occult Mixed Cryoglobulinemic Vasculitis

A 53-year-old man with active hepatitis C and cirrhosis presented with a vasculitic rash, myalgias, and fatigue, and was found to have an elevated cardiac troponin I up to 15.7 ng/mL with normal electrocardiogram, echocardiogram, and coronary angiogram prior to being discharged. Subsequently, during a similar presentation to another academically affiliated hospital, the patient had a normal cardiac troponin T (< 0.01 ng/mL). Upon his third presentation with significantly elevated troponin I to 15.98 ng/mL, the patient was found to have cryoglobulinemic vasculitis and elevated rheumatoid factor due to active hepatitis C, causing interference with the troponin I immunoassay. In conclusion, troponin I assays may have high false-positive values due to interference by rheumatoid factor and/or a polyclonal antibody found in cryoglobulinemia.

Remnant cholesterol predicts periprocedural myocardial injury following percutaneous coronary intervention in poorly-controlled type 2 diabetes

BackgroundRemnant cholesterol (RC) is receiving increasing attention regarding its relation to cardiovascular risk. Whether RC is associated with periprocedural myocardial injury (PMI) following percutaneous coronary intervention (PCI) in type 2 diabetes (T2D) is currently unknown. MethodsWe prospectively enrolled 1182 consecutive T2D patients who were scheduled for PCI but with baseline normal preprocedural cardiac troponin I (cTnI). Patients were divided according to their glycemic control status: group A [glycated hemoglobin (HbA1c)<7%, n=563] and group B (HbA1c≥7%, n=619). PMI was evaluated by cTnI analysis within 24h. The associations of preprocedural RC and the RC to high-density lipoprotein cholesterol ratio (RC/HDL-C) with PMI were investigated. ResultsThe associations of RC and RC/HDL-C with PMI were observed in group B (both p<0.05) but not in group A (both p>0.05). Patients in group B, a 1-SD increase of RC produced 30% and 32% increased risk for postprocedural cTnI>3× upper limit of normal (ULN) and >5×ULN, respectively. The odds ratios for RC/HDL-C were the highest compared with any cholesterol fractions including total cholesterol (TC)/HDL-C, low density lipoprotein cholesterol (LDL-C)/HDL-C, nonHDL-C/HDL-C, and triglyceride/HDL-C with 1.43 [95% confidence interval (CI): 1.10–1.88] for >3× ULN and 1.49 (95% CI: 1.13–1.97) for >5× ULN. However, no such associations were found in group A. Furthermore, patients with RC >27.46mg/dL (third tertile) [RC≤14.15mg/dL (first tertile) as reference] were associated with a 1.57-fold and 2-fold increased risk for >3× ULN and >5× ULN in group B, respectively. ConclusionsRC and RC/HDL-C might be valuable, independent predictors for PMI in poorly-controlled diabetic patients undergoing PCI.

Correlation of cardiac troponin I levels with infective endocarditis & its adverse clinical outcomes

BackgroundTo study the association of increased cardiac troponin I levels in infective endocarditis (IE) with its adverse clinical outcomes including in-hospital mortality, perivalvular invasive infection and central nervous system events. MethodsA prospective cohort study of 26 patients comprising of 19 males and 7 females with an average age of 28years diagnosed with IE using Modified Duke Criteria were taken. A blood sample was drawn from each patient and all samples were analyzed for quantitative estimation of troponin I using ELISA technique. A cardiac troponin I level >1.0ng/ml was considered increased. All data was analyzed by independent- samples t test using SPSS Version 16.0. ResultsAll 26 patients had vegetations diagnosed on echocardiography. Of the 26 patients, 9 (35%) had elevated cardiac troponin I levels and 17 patients (65%) had normal cardiac troponin I levels. Of the 9 patients who had elevated cardiac troponin I levels, 7 (77.78%) had adverse clinical outcomes, the level of statistical significance being p value<0.0002. Of the 17 patients with normal cardiac troponin I levels, only 1 (5.88%) had adverse clinical outcome, the level of statistical significance being p value<0.0001. ConclusionPatients with IE and increased cardiac troponin I levels have worse prognosis with increased incidence of adverse clinical outcomes than those with IE and normal cardiac troponin I levels reflecting potential of cardiac troponin I as a prognostic marker in IE.

Incidentally Raised Cardiac Troponin I Has a Worse Prognosis in Older Patients Compared to Those with Normal Cardiac Troponin I and Patients with Acute Coronary Syndrome: A Cohort Study

Background: Incidentally elevated cardiac troponin I (cTnI) levels are common in acutely unwell older patients. However, little is known about how this impacts on the prognosis of these patients. Objective: We aimed to investigate whether incidentally elevated cTnI levels (group 1) are associated with poorer outcome when compared to age- and sex-matched patients without an elevated cTnI level (group 2), and to patients diagnosed with acute coronary syndrome (group 3). Patients and Methods: This prospective, matched cohort study placed patients ≥75 years old who were admitted to a University teaching hospital into groups 1-3, based on the cTnI levels and underlying diagnosis. Outcomes were compared between the groups using mixed-effects regression models and adjusted for renal function and C-reactive protein. All-cause mortality at discharge, at 1 month and 3 months, alongside the length of hospital stay (LOS), were recorded. Results: In total, 315 patients were included, with 105 patients in each of the 3 groups. The mean age was 84.8 ± 5.5 years, with 41.9% males. All patients were followed up for 3 months. The percent all-cause mortality at discharge and the LOS for groups 1, 2 and 3 were 12.4, 3.8 and 8.6% and 11.2, 8.5 and 7.7 days, respectively. Group 1 had significantly increased mortality at 3 months [odds ratio (OR) 2.80, 95% confidence interval (CI) 1.12-6.96; p = 0.040] and LOS (OR 1.39, 95% CI 1.08-1.79; p = 0.008) compared to group 2 and did not differ significantly when compared to 3-month mortality (OR 2.39, 95% CI 0.91-6.29; p = 0.079) or LOS (OR 1.26, 95% CI 0.96-1.66; p = 0.097) in group 3. Conclusion: There is a significant association between an incidental rise in cTnI level with mortality and LOS in older patients. Further research is required to evaluate whether a more systematic management of these patients would improve the prognosis.

Below normal pre-procedural cardiac troponin I levels are associated with an adverse prognosis after percutaneous coronary interventions.

To evaluate the prognostic implications of baseline cardiac troponin (cTn) values in the normal range in stable coronary artery disease (CAD) patients successfully treated with percutaneous coronary intervention (PCI). We investigated the correlation between pre-procedural cTnI levels and major clinical adverse events at three years of follow-up in 1,063 consecutive stable CAD patients with normal baseline cTnI levels, successfully treated with PCI. Patients with pre-procedural cTnI levels in the upper tertile showed an increased long-term risk of overall death (HR 3.17, 95% CI: 1.62 to 6.21; p=0.0001), cardiac death (HR 5.09, 95% CI: 2.30 to 11.25; p=0.002), myocardial infarction (MI) (HR 2.34, 95% CI: 1.45 to 3.76; p=0.003) and target vessel failure (TVF) (HR 1.91, 95% CI: 1.28 to 2.84; p=0.006). Pre-procedural cTnI levels remained significantly correlated after adjustment for clinical and angiographic findings. Analysis of pre-PCI values eliminated any association of post-PCI values with prognosis. In stable CAD patients successfully treated with PCI, pre-procedural cTnI levels, in the upper limits of the normal range, are associated with hard cardiac endpoints.

Multimarker risk stratification approach and cardiovascular outcomes in patients with stable coronary artery disease undergoing elective percutaneous coronary intervention

AimsWe studied the utility of multimarker risk stratification approach to predict cardiovascular outcomes in patients with stable coronary artery disease, undergoing elective percutaneous coronary intervention (PCI). MethodsWe prospectively evaluated 302 consecutive patients with stable coronary artery disease and normal CPK-MB and cardiac troponin T levels, and who underwent elective PCI at our institution. The following cardiac biomarkers were measured before and between 12 and 24h post-procedure: CK-MB, cardiac troponin T, hs-CRP, and NT-ProBNP. Patients were followed up for a minimum of 6 months. ResultsPost-PCI, CPK-MB levels were elevated but below myocardial infarction (MI) range in 70 patients (23%), and in the MI range in 6 patients (2%). Troponin T levels were detectable but below the 99th percentile (microleak) in 32 patients (10.6%) and elevated above the 99th percentile (periprocedural MI) in 104 patients (34.4%). At 9 months’ follow-up, 1% died, 2% had stable angina, 10.3% had non-fatal MI, and 87.7% remained asymptomatic. There was no significant difference in clinical events among groups stratified by elevation of one biomarker or multiple biomarkers. ConclusionSingle or multiple biomarker strategy in patients with normal baseline biomarkers failed to predict major cardiac events after PCI over medium-term follow-up.

The incremental value of stress testing in patients with acute chest pain beyond serial cardiac troponin testing

ObjectiveIn patients with acute chest pain and normal range cardiac troponin (cTn), accurate risk stratification for acute coronary syndrome is challenging. This study assesses the incremental value of stress testing...

Relationship of high-density lipoprotein cholesterol with periprocedural myocardial injury following elective percutaneous coronary intervention in patients with low-density lipoprotein cholesterol below 70 mg/dL.

BackgroundRecent data showed inconsistent association of high‐density lipoprotein cholesterol (HDL‐C) with cardiovascular risk in patients with different levels of low‐density lipoprotein cholesterol (LDL‐C) or intensive statin therapy. This study sought to determine the relationship of HDL‐C with periprocedural myocardial injury following elective percutaneous coronary intervention (PCI) across a range of LDL‐C levels, especially in patients with LDL‐C <70 mg/dL.Methods and ResultsWe enrolled 2529 consecutive patients with normal preprocedural cardiac troponin I (cTnI) who underwent elective PCI. The association between preprocedural HDL‐C and periprocedural myocardial injury was evaluated across LDL‐C levels, especially in patients with LDL‐C <70 mg/dL. The HDL‐C level was not predictive of periprocedural myocardial injury across the entire study cohort. However, among patients with LDL‐C <70 mg/dL, a 1 mg/dL increase in HDL‐C was associated with a 3% reduced risk for postprocedural cTnI above 1×upper limit of normal (ULN) (odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.004), a 3% reduced risk for postprocedural cTnI above 3×ULN odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.022), and a 3% reduced risk for postprocedural cTnI above 5×ULN (odds ratio: 0.97; 95% CI: 0.95 to 0.99; P=0.017). The relation between plasma HDL‐C level and risk of postprocedural cTnI elevation above 1×ULN, 3×ULN, and 5×ULN was modified by LDL‐C level (all P for interaction <0.05).ConclusionsHigher HDL‐C levels were associated with reduced risk of periprocedural myocardial injury only in patients with LDL‐C <70 mg/dL.

Association of preprocedural low-density lipoprotein cholesterol levels with myocardial injury after elective percutaneous coronary intervention.

Lower levels of low-density lipoprotein cholesterol (LDL-C) are associated with less cardiovascular risk in patients with coronary artery disease. To assess whether lower preprocedural LDL-C levels are associated with less risk of periprocedural myocardial injury in patients undergoing elective percutaneous coronary intervention (PCI). We enrolled 2529 consecutive patients with normal preprocedural cardiac troponin I (cTnI) who successfully underwent elective PCI. The association between preprocedural LDL-C levels and peak cTnI levels within 24 hours after PCI was evaluated. Preprocedural LDL-C levels were correlated to postprocedural cTnI levels (r = 0.059, P = .003). In the multivariable model, preprocedural LDL-C levels between 70 and 99 mg/dL were associated with less risk of postprocedural cTnI elevation above 1 × upper limit of normal (ULN) (odds ratio [OR]: 0.804; 95% confidence interval [CI]: 0.663-0.975; P = .027) up to 15 × ULN (OR: 0.709; 95% CI: 0.530-0.949; P = .021) compared with preprocedural LDL-C levels ≥100 mg/dL. Moreover, preprocedural LDL-C levels <70 mg/dL were more strongly associated with less risk of postprocedural cTnI elevation above 1 × ULN (OR: 0.736; 95% CI: 0.584-0.927; P = .009) up to 15 × ULN (OR: 0.655; 95% CI: 0.452-0.950; P = .026). Lower preprocedural LDL-C levels were associated with less risk of periprocedural myocardial injury in patients undergoing elective PCI.

Positive Association of Coronary Calcium Detected by Computed Tomography Coronary Angiography with Periprocedural Myocardial Infarction

BackgroundPeriprocedural myocardial infarction (PMI) may occur in approximately 5% to 30% of patients undergoing percutaneous coronary intervention. Whether the morphology of coronary plaque calcium affects the occurrence of PMI is unknown.Materials and MethodsA total of 616 subjects with stable angina and normal baseline cardiac troponin I levels who had undergone computed tomography angiography (CTA) were referred to elective percutaneous coronary intervention. The morphology of coronary calcium was determined by CTA analysis. PMI was defined as an elevation in 24-h post-procedural cardiac troponin I levels of > 5 times the upper limit of normal with either symptoms of myocardial ischemia, new ischemic electrocardiographic changes, or documented complications during the procedure. Logistic regression was performed to identify the effect of the morphology of coronary calcium on the occurrence of PMI.ResultsAccording to the presence or morphology of coronary calcium as shown by CTA, 210 subjects were grouped in the heavy calcification group, 258 in the mild calcification group, 40 in the spotty calcification group and 108 in the control group. The dissection rate was significantly higher in the heavy calcification group than in the control group (7.1 % vs. 1.9%, p = 0.03). The occurrence of PMI in the heavy calcification group was significantly higher than that in the control group (OR 4.38, 95% CI 1.80–10.65, p = 0.001). After multivariate adjustment, the risk of PMI still remained significantly higher in the heavy calcification group than in the control group (OR 4.04, 95% CI 1.50–10.89, p = 0.003).ConclusionsThe morphology of coronary calcium determined by CTA may help to predict the subsequent occurrence of PMI. A large amount of coronary calcium may be predictive of PMI.

Use of Antiplatelet Drugs in the Treatment of Acute Coronary Syndromes

Patients with unstable angina pectoris/non-ST-elevation myocardial infarction (NSTEMI) should be treated with dual antiplatelet therapy with the use of aspirin plus either clopidogrel, prasugrel, or ticagrelor depending on the clinical circumstances as discussed in this article. If ticagrelor is used, the dose of aspirin must not exceed 100 mg daily. Prasugrel must not be used in patients with a history of stroke or transient ischemic attack. Platelet glycoprotein IIb/IIIa inhibitors should not be used as part of triple antiplatelet drug therapy if there is an increased risk for bleeding or in non-high-risk patients such as those with a normal baseline cardiac troponin level, nondiabetics, and those aged 75 years and older in whom potential benefit may be significantly offset by the potential risk of bleeding. Clinical trial data in patients with acute coronary syndromes do not support the use of intravenous cangrelor or oral voraxapar in the treatment of these patients.

Introduction of an accelerated diagnostic protocol in the assessment of emergency department patients with possible acute coronary syndrome: The Nambour Short Low‐Intermediate Chest pain project

Emergency physicians can feel pressured by opposing forces of clinical reality and the need to publish successful key performance indicators in an environment of increasing demands and cost containment. This is particularly relevant to management of patients with undifferentiated chest pain and possible acute coronary syndrome. Unreliability of clinical assessment and high risk of adverse outcomes for all concerned exist, yet national guidelines are at odds with efforts to reduce ED crowding and access block. We report findings from the Nambour Short Low-Intermediate Chest pain risk trial, which safely introduced an accelerated diagnostic protocol with reduced ED length of stay and high patient acceptability. Over a 7-month period, there were no major adverse cardiac events by 30 days in 19% of undifferentiated chest pain presentations with possible acute coronary syndrome discharged after normal sensitive cardiac troponin taken 2 h after presentation and scheduled to return for outpatient exercise stress test.

Ischaemia modified albumin in patients with acute coronary syndrome and negative cardiac troponin I

Background. Approximately 40–60% of patients with acute coronary syndrome (ACS) have normal cardiac troponin I (cTnI) concentrations on admission. Ischaemia modified albumin (IMA) has been suggested as a new biomarker of myocardial ischaemia. Methods. A total of 43 patients presenting with symptoms suggestive of ACS but with normal (< 0.1 μg/L) cTnI concentrations and 45 healthy subjects were studied. The patients from the study group were divided into two groups: STEMI (n = 28) and NSTEMI (n = 15). All these patients were undergoing percutaneous coronary intervention (PCI) with stenting. The concentrations of cTnI, myoglobin and IMA were determined on admission and 4 h after PCI. Results. Mean (SD) IMA concentrations were higher in patients with ACS (114.39 ± 25.18 U/ml) as compared to the control group (96.24 ± 6.28 U/ml, p < 0.005). IMA concentrations ≥ 104.0 U/ml demonstrated 72.1% sensitivity and 75.6% specificity for the diagnosis of ACS. The area under the receiver operator characteristic curve was 0.766 (95% CI 0.664–0.868) for ACS patients (NSTEMI + STEMI). In both groups increased median (IQR) cTnI concentration after PCI was observed (STEMI patients to 65.4 (10.9–106.9) μg/L and NSTEMI to 17.6 (0.77–84.0) μg/L). In contrast, no increase in IMA concentration was observed. Conclusions. IMA may be a useful biomarker for the identification of ACS patients presenting with typical acute chest pain and/or abnormal electrocardiograms but negative cTnI.